How to unwrap TRs if they got wrapped in a Tbody by the DOMParser

swap.js

// unwrap TRs if they got wrapped in a tbody by the parser
{
    let trsCountInResponseText = 0;
    let trsCountInResponseFragment = 0;
    if (responseText.indexOf('<tr') !== -1) {
        var regExp = new RegExp('<tr', 'gim');
        trsCountInResponseText = (responseText.match(regExp) || []).length;

        for (const elt of responseElts) {
            if (elt.tagName === 'TR') {
                trsCountInResponseFragment += 1;
            }
        }
    }
    if (trsCountInResponseText > 0 && trsCountInResponseFragment === 0) {
        // parser wrapped rows in a tbody
        // we didn't ask for that, so we want to unwrap the rows, to be able to apply their swap attributes
        console.log('trsCountInResponse', trsCountInResponseText, 'trsCountInResponseFragment', trsCountInResponseFragment);
        let tBodyInResponseFragment = undefined;
        let tBodyIndexInResponseFragment = -1;

        for (let i = 0; i < responseElts.length; i++) {
            const elt = responseElts[i];
            if (elt.tagName === 'TBODY') {
                tBodyInResponseFragment = elt;
                tBodyIndexInResponseFragment = i;
                break;
            }
        }
        if (tBodyInResponseFragment !== undefined) {
            const trs = tBodyInResponseFragment.children;
            // delete tbody and insert trs instead
            console.log(`replacing TBODY in response fragment with ${trs.length} TRs`);
            responseElts.splice(tBodyIndexInResponseFragment, 1, ...trs);
        }
    }
}